1. Technical Field
This invention relates to electrosurgical instruments. More particularly, the invention relates to electrosurgical instruments that facilitate the performance of various procedures or reduce the amount of fatigue experienced by users performing the procedures.
2. The Relevant Technology
As is known to those skilled in the art, modern surgical techniques typically employ radio frequency (RF) power to cut tissue and coagulate bleeding encountered in performing surgical procedures. For a historical perspective and details of such techniques, reference is made to U.S. Pat. No. 4,936,842, issued to D'Amelio et al., and entitled “Electroprobe Apparatus,” the disclosure of which is incorporated by this reference.
As is known to those skilled in the medical arts, electrosurgery is widely used and offers many advantages including the use of a single surgical instrument for both cutting and coagulation. A monopolar electrosurgical generator system has an active electrode, such as in the form of an electrosurgical instrument having a hand piece and a conductive electrode or tip, which is applied by the surgeon to the patient at the surgical site to perform surgery and a return electrode to connect the patient back to the generator.
The electrode or tip of the electrosurgical instrument is small at the point of contact with the patient to produce an RF current with a high current density in order to produce a surgical effect of cutting or coagulating tissue. The return electrode carries the same RF current provided to the electrode or tip of the electrosurgical instrument, thus providing a path back to the electrosurgical generator.
To make the electrical connection for the RF current between the electrosurgical generator and the electrosurgical instrument, a cable having an electrically conductive core extends from the electrosurgical generator to the electrosurgical instrument. The cable may also include a cord with additional conductors. The cord provides a connection for transmitting control signals from the electrosurgical instrument to the electrosurgical generator. The control signals may be used to cause the generator to deliver RF currents to the electrosurgical instrument for different cutting modes such as cut, coagulate, and cut-coagulate blend.
When an electrosurgical instrument is used for cutting or coagulation, smoke is commonly produced. A surgeon or assistant uses a separate smoke evacuation device to remove the smoke from the surgical field. Smoke evacuation devices commonly include a suction wand connected to a vacuum device via tubing. The surgeon or assistant holds the suction wand close to the surgical site and the smoke is drawn into the suction wand and through the tubing. However, using a smoke evacuation device separate from the electrosurgical instrument is not ideal. Using a separate smoke evacuation device requires additional hands and instruments near the surgical site, which can obscure the surgeon's view of the surgical site and reduce the room available around the surgical site for the surgeon to move.
As a result, combination electrosurgical instrument and smoke evacuation devices have been developed. These combination devices often include a hand piece that can receive an electrode or tip in a distal end thereof for performing electrosurgical procedures. The hand piece is connected to a generator via a power cable to convey RF current to the electrode or tip. Additionally, a smoke evacuation hose is connected between the hand piece and a vacuum to draw smoke away from the surgical site. In some cases, the power cable runs through a portion of the smoke evacuation hose.
The power cables and smoke evacuation hoses have certain flexibility and weight characteristics that limit the ability of the physician during a surgical procedure. For example, the weight/moment-arm effect and drag of the power cable and/or the smoke evacuation hose as well as the connection location(s) of the power cable and/or smoke evacuation hose to the electrosurgical instrument limit the physician's ability to continually hold and use the electrosurgical instrument. The electrode or tip is received within one end (distal end) of the hand piece (commonly referred to as a pencil) and the power cable and/or smoke evacuation hose typically enter into the opposite end (proximal end) of the hand piece. As the physician manipulates the electrosurgical instrument during a surgical procedure, the weight of the power cable and/or smoke evacuation hose continually pulls on the proximal end of the hand piece. More specifically, as the physician moves his or her wrist or adjusts the orientation of the electrosurgical instrument with his or her fingers so as to bring the electrode into contact with the patient's tissue, the weight of the power cable and/or smoke evacuation hose resists the physician's movement. The constant resistance or drag created by the power cable and/or smoke evacuation hose can cause the physician to become fatigued during a surgical procedure that requires extensive and continual use of the electrosurgical instrument.
Additionally, many electrosurgical procedures are performed on very sensitive parts of the body, such as on or around the eyes. When performing such procedures, the physician must control the movements of the electrode with great precision and accuracy. The resistance or drag created by the power cable and/or smoke evacuation hose can make it more difficult for the physician to be as precise and accurate. For instance, when moving the electrosurgical instrument to make a delicate incision, the physician must accurately compensate for the resistance from the power cable and/or smoke evacuation hose. If the physician overcompensates, an incision that is too deep or too long can result. Alternatively, if the physician undercompensates, multiple passes may be required to achieve the desired incision. Furthermore, the fatigue caused by the resistance from the power cable and/or smoke evacuation hose can adversely affect the physician's ability to accurately compensate for the resistance from the power cable and/or smoke evacuation hose.
Furthermore, some existing combination electrosurgical instrument and smoke evacuation devices include an extendable portion, typically in the form of an enclosed tube, which can be selectively extended from the distal end of the hand piece. When the extendable portion is extended, the device is able to reach deeper into a surgical site to evacuate smoke. The extendable portion is typically slidably disposed within an internal chamber in the hand piece. A seal is used between the extendable portion and the internal chamber to prevent smoke from escaping the hand piece at the distal end. Similarly, a seal is used at the proximal end of the hand piece, where the smoke evacuation hose is connected to the internal chamber, to prevent smoke from escaping from the hand piece at the proximal end. Thus, the internal channel acts as part of a flow conduit through which the smoke is evacuated.
Combination electrosurgical instrument and smoke evacuation devices that utilize the foregoing internal chamber design have a number of drawbacks. For instance, this arrangement usually increases the complexity of the hand piece design, assembly, and physical size. By way of example, seals must be properly disposed in both the proximal and distal ends of the hand piece in order to seal off the internal chamber and maintain the vacuum pressure therein. Additionally, the ergonomics of the hand piece are also hindered because the hand piece must remain linear to accommodate the extending portion. Still further, the smoke evacuation hose must be connected at the proximal end of the hand piece, which leads to the aforementioned undesirable resistance and moment arm effects.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.